I see to many built subaru motors fail, so I'm trying to make sure I build it the best cost effective way as possible. closed deck seems like the toughest way. oil enquirers should be fine.

They fail typically from user error, shortcuts in the build process or put together too loose. You can spend tens of thousands of dollars on parts and sill put it together wrong, miss shift, over rev, lack of oil..... ect. Most people out there dont want to tell the whole story as to why it failed, they blame the tuner, the builder or anyone else they can before they would ever say they miss shifted or over reved the piss out of an engine.